Coupling device for ski binding cable



NOV. 1, 1966 BERCHTOLD ET AL 3,282,597

COUPLING DEVICE FOR SKI BINDING CABLE Filed March 13, 1964 4Sheets-Sheet l FIG. 2

Nov. 1, 1966 L. BERCHTOLD ET AL 3,282,597

COUPLING DEVICE FOR SKI BINDING CABLE Filed March 15, 1964 4Sheets-Sheet 2 NOV. 1, 1966 BERCHTOLD ET AL 3,282,597

COUPLING DEVICE FOR SKI BINDING CABLE Filed March 13, 1964 4Sheets-Sheet 3 FIG. 77

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AJ ZTr 7295 NOV. 1, 1966 BERCHTQLD ET AL 3,282,597

COUPLING DEVICE FOR SKI BINDING CABLE Filed March 13, 1964 4Sheets-Sheet 4 FIG. 12 43 a FIG. 13

United States Patent COUPLING DEVICE FOR SKI BINDING CABLE LudwigBerchtold, Bergstrasse 85, Krailling, near Munich,

Germany, and Albert Schuster, Muuchner Strasse 15,

Planegg, near Munich, Germany Filed Mar. 13, 1964, Ser. No. 351,811Claims priority, application Germany Mar. 22, 1963, B 71,255; Feb. 6,1964, B 75,315 Claims. (Cl. 280-11.35)

Coupling devices for detachably coupling the ends of a ski bindingcable, which is split behind the heel of the boot, are known, in whichthe coupling members are separated from each other in response to anexcessive tension acting on the cable in the longitudinal direction ofthe ski so that the foot is released in the case of a frontal fall ofthe skier. In the case of torsional falls, in which the leg of the skieris subjected to torsion, and in the case of other lateral stresses,these known coupling devices release the leg only if a sufficientlystrong component of force in the longitudinal direction of the ski isproduced by the torsional or lateral force. It is an object of theinvention to provide a coupling device which releases the foot in thecase of a lateral movement of the skiing boot, i.e., in the case oftwisting falls, and otherwise reliably connects the cable ends when thebinding is applied. In a development of the invention, the couplingdevice is to be designed in such a manner that it releases the foot inthe case of twisting and frontal falls.

In a coupling device for detachably connecting the ends of a ski bindingcable which is split behind the heel of the boot, this object isaccomplished according to the invention in that a yoke conforming to thecurvature of the heel is bisected behind the heel and the two halveshave hook portions, which interengage and are locked against a movementat right angles to the plane of the coupling members when the binding isclosed and the interengaging surfaces of these hook portions are forcedtogether and are approximately parallel or only slightly inclined to thelongitudinal center line, each of the coupling members having a stop,which is spaced from the interengaging surfaces of the hook portions,and these stops being arranged to be forced toward each other by a forceacting on one of the cable ends in a lateral direction away from theski, and to form a fulcrum for a pivotal movement of the couplingmembers, whereby the hook portions are disengaged. When the binding isbeing used, the yoke halves are forced against the heel by the cabletension acting in the longitudinal direction of the ski. As a result,the hook portions are particularly firmly interengaged because the heelforces the front hook portion into the recess of the rear hook portion,and the support of the yoke halves against the heel causes the forcesacting on the yoke halves in the longitudinal direction of the ski to bedeflected and produce laterally directed forces, which promote theinterengagement of the hook portions. In response to a lateraldisplacement of the heel of the boot, the stop faces of the two couplingmembers are forced against each other, and a further action of a lateralforce will result in a pivotal relative movement of the coupling membersabout the point of contact of the stop faces acting as abutments so thatthe hook portions are disengaged and the binding entirely releases thefoot.

In a particularly simple manner, the means for locking the hook portionsagainst a movement at right angles to the plane of the coupling elementsmay consist of guide plates, which are connected to one hook portion andengage the side faces thereof and guide the other hook portion.According to another advantageous suggestion of the invention, a detentdevice is provided for a readily releasable retention of the hookportions in their interengaging position. To this end, at least one ofsaid guide plates may be resiliently connected to the associated hookportion and may be provided with a bulge, which coacts with a detentsocket of the other hook portion. Whereas a readily releasable retentionof the hook portions in their interengaging position is not required forthe function of the coupling device according to the invention, thisdetent arrangement facilitates substantially the application of thebinding cable because the coupling elements would otherwise be retainedin their interengaging position only by the tension of the binding cableand the reaction pressure of the heel of the boot and would have to beheld together by hand until the cable has been tensioned.

In order to obtain the safety function of the coupling according to theinvention also in the case of frontal falls, the rear hook portion,considered in the longitudinal direction of the ski, may be pivoted tothe associated coupling member in such a manner that this hook portionwill release the other hook portion by a rearward pivotal movement, andthe pivoted hook portion may be locked by a locking device, whichreleases the pivotal movement when a predetermined cable tension isexceeded. As the rear hook portion, considered in the longitudinaldirection of the ski, is subjected by means of the front hook portion tothe action of the cable tension and of the reaction pressure exerted bythe heel of the boot, this rear hook portion will be pivotally movedrearward-1y as soon as it can pivotally move relative to the associatedcoupling member bearing on the heel. As a result, the other hook portionis disengaged from the pivoted hook and the heel of the boot isreleased.

In a preferred embodiment, the pivoted hook portion may have a stop,which locks the hook portion against a pivotal movement when this stopengages a counterstop arranged on the associated coupling member,whereas the counterstop is displaceable in the coupling member independence on the cable tension to such an extent that the stop of thehook portion is released. Each coupling mem-. ber may have in knownmanner an abutment surface for a coil spring, which surrounds the rearend of the cable and against which the cable is supported by a springwasher, the counterstop consisting of a slide which is connected to thespring washer of its coupling member. The foot will be released as soonas the respective coil spring has been compressed by the cable tensionto such an extent that the slide has been moved out of the path of thepivotal movement of the stop of the associated hook portion. In thisconnection it is particularly suitable if the position of the sliderelative to the spring washer is ad -justable so that the releasingmoment or, in other words,

the spring displacement required for the release, can be individuallydetermined in dependence on the weight of the skier and, if desired, onother circumstances.

In a'modification of the embodiment which has just been discussed, thecounterstop may be displaceable in the associated coupling memberagainst the force of a return spring under the action of a tensionelement, which is secured to a binding part which is inelasticallyconnected to the ski, whereas this tension element is movable relativeto the resiliently fixed cable. This tension element may consist of athin wire, a filament of plastics material, or the like, and may bedisposed inside the protective sheath of the corresponding cablesection, but is directly connected to the front tightener, to which thecable is connected by coil springs. The effective length'of the tensionelement may be adjustable for determining that spring displacement whichis required for a release of the coupling members from each other in thecase of a frontal fall.

In a further embodiment, the locking device may consist of a detentdevice, which is effective between the movable hook portion and theassociated coupling half and which is adjustable with respect to itsretaining pressure.

Various embodiments of the invention will be explained more fully by wayof example in the following description with reference to the drawing,in which FIG. 1 is a side elevation showing a first embodiment of thecoupling device according to the invention and FIG. 2 is a top planshowing the coupling device of FIG. 1, the parts which are covered'by-the spring plate being indicated in broken lines,

FIG. 3 is a top plan view similar to FIG. 2 and shows the releasedcoupling device,

FIG. 4 shows another embodiment in a top plan View, partly in section,

FIG. 5 shows the embodiment of FIG. 4 with the coupling released by afrontal fall,

FIG. 6 is a sectional view taken on line A-B of FIG. 4, I FIG. 7 asectional view taken on line C-D of FIG. 4,

FIG. 8 a sectional view taken on line E-F of FIG. 4,

FIG. 9 a top plan view showing another embodiment of the coupling deviceaccording to the invention,

FIG. 10 a diagrammatic view showing the associated tightcner andthemeans for spring-connecting the binding cable to this tightener,

FIG. 11 is a side elevation similar to FIG. 8,

FIG. 12 a top 'plan view showing a final embodiment,

FIG. 13 a side elevation, partly in section, showing the embodiment ofFIG. 12, and

FIG. 14 the use of the embodiment of FIGS. 12 and 13 with a short heelcable, which is secured to the side faces of the ski.

As is apparent from FIG. 2, the coupling device according to theinvention consists of the coupling members 1 and 2, which form the twoparts of a yoke, which engages the heel of the skiing boot 7 at A and Band conforms to the shape of the heel. The cable sections 3 and 10 aresecured to the front ends of the coupling sections 1 and 2. The couplingmember 1 comprises a hook portion 8 and the coupling member 2 comprisesa hook portion 14. When the hook portions 8 and 14 are interengaged, adropping of the coupling member 1 with the hook portion 8 or an upwardmovement of the same is prevented by the resilient guide plate 4 (seeFIG. 1), which is U-shaped in cross-section and formed with a bulge 5.The spring plate is riveted to the coupling member 2 at 9. The hookportion 8 has a detent socket 6, which is engaged by the bulge 5 whenthe coupling device is being assembled. This arrangement ensures thatthe coupling members 1 and 2 will remain connected to each other evenwhen the cable 3, 10 has not yet been tightened, unless the couplingmembers are pulled apart against the very small retaining force of thedetent device 5, 6.

' The two coupling members are provided with co-acting stops 13 and 15,which are spaced from the inter-engaging parts of the hooked portions 8and 14. These stops are arranged to strike on each other when the hookportion 14 of the coupling member 2 is in snug engagement.

with the recess in the coupling member 1. If the coupling deviceaccording to the invention is used with a boot which has a narrower heelthan that which is shown, the hook portion 14 will not completely enterthe recess in the coupling member 1 and the stop faces 13 and 15 willnot contact during the normal use of the binding.

When the cable 3, 10 is tensio-ned in the direction of the arrows x 'bymeans of a front tightener, which is not shown, the support of the yokehalves 1 and 2 at A and B against the heel of the skiing boot 7 willgive rise to lateral forces, rather than a forwardly directed tension,in

the region in which the hook portions 8 and 14 interenv gether at C.This effect will also be obtained if the heel of the skiing boot issmaller than that shown in the drawing. In this case the stop faces willnot contact during the normal use of the binding but the interengagementof the hook portions 8 and 14 at C will be retained. Thisinterengagement will be obtained regardless of the presence or absenceof the detent socket 6 and of the bulge 5 on the spring plate 4. Evenwhen the two coupling members 1 and 2 are very loosely fitted togetherbefore the cable 3, 10 is tensioned, a firm connection will be effectedby the tension acting in the direction x.

When a twisting fall or another strong lateral stress causes a lateralforce in the direction or y to act on the heel and on the binding cable3, 10, and down-pulls 11, 12 are provided, the cable will be torn out ofthe corresponding down-pull. For this purpose this down-pull must be sodesigned in known manner that the cable can slip out under a stronglateral force. As is clearly apparent from the drawing, the lateralforce causes the stop faces 13 and 15 to be forced together so that theyform a fulcrum for the ensuing pivotal relative movement of the couplingmembers 1, 2, whereby the hook portion 8 of the coupling member 1 ismoved out of the recess in the coupling member 2 so that the twocoupling members are disengaged. The binding has now entirely releasedthe skiing boot 7 and the danger to the leg has been eliminated. The useof the coupling device according to the invention is particularlyadvantageous when pivoted front safety jaws are provided because suchpivoted jaws may restrain the front portion of the foot during atwisting fall and permit only of a rotation of the foot about an axiswhich extends approximately through the heel region whereas the heel isstill restrained, at least at the beginning of the release movement.

Hence, the surprising mode of operation of the invention residesessentially in that the tension x acting in the longitudinal directionis deflected as a result of the support of the coupling members 1 and 2at a and b so that lateral forces tending to hold the two hook portionsin firm interengagement become effective in the region 0 during thenormal use of the binding, whereas lateral forces acting on the heelwill displace the points of support from c to the region d at the stopfaces 13 and 15, which will then determine the fulcrum of the twocoupling members so that the hook portions 8 and 14 will be positivelyseparated from each other.

In the embodiment shown in FIGS. 4 to 8, the design of the couplingmembers 1 and 2 is basically the same as in the embodiment justdescribed. The spring plate 4 has been replaced by thicker plates 30 and'31, which are secured to the coupling member 2. The rear hook portion21, considered in the longitudinal-direction of the ski, is rotatablymounted at 24 between the plates 30 and 31 and has at its portion whichis in front in the drawing a projecting stop 25, which in the positionshown in FIG. 4 engages the counterstop 27 and is locked by the sameagainst rotation. On the other side, the stop 25 engages the edge 26 ofthe plate 30. In this position, the hook portion 21 is entirely rigidlyconnected to the coupling member 2. As is shown on the drawing, thecounterstop 27 consists of a slide, which has at its rear end an angleplate, by means of which it is vertically adjustable by the screw 28.The cable nipple 29 serving as a spring washer has a tapped bore, whichreceives the adjusting screw 28 so that the slide 27 follows themovements of the spring washer 29 against the force of the compressionspring 22. The spring 22 and the similar spring 23 of the couplingmember 1 abut at the end of their protecting sleeves and permit of alimited movement of the heel at right angles to the surface of the ski.By such a movement, the springs 22 and 23 are compressed and the springwashers are moved relative to the coupling members 1 and 2. During thismovement, the spring washer 29 will drive the slide 27. In the case ofexcessively high stresses in the longitudinal direction of the ski, suchas occur during a frontal fall, the slide 27 assumes the position shownin FIG. 5. In this position, the slide 27 releases the stop 25 so thatthe hook portion 21 is immediately pivotally moved in response to thereaction pressure of the skiing boot acting in the direction x, and thehook portion 8 is released. The spring displacement of the spring 22required for a release of the hook portion 21 by the slide 27 can be adjusted by means of the adjusting screw 28. This embodiment comprisesalso means for easily detachably locking the hook portion 8 relative tothe plate 30 so that the coupling portions need not be held in theirinterengaging position by hand when the binding is being applied. Duringa twisting fall, the coupling device according to FIGS. 48 is releasedin the manner which has already been described with reference to FIGS. 1to 3. In this case the hook portion 21 remains in the position shown inFIG. 4 whereas the coupling members are pivotally moved about the stopfaces 13 and 15 to disengage the hook portions 8 and 21 from each other,as shown in FIG. 5.

In the embodiment shown in FIGS. 9 to 11, the springs of the cable loopare provided in the previously usual manner between the cable and atension element connected to the front tightener 36 of the ski ratherthan being disposed behind the heel and connected to the coupling deviceas in the embodiment just described. In order to ensure neverthleless arelease of the coupling device in the case of a frontal fall independence on the spring displacement, a rope 34 consisting, e.g., ofplastics material, is secured to the tension element, withoutinterposition of the coil springs 37 or 38. The effective length of thisrope can be adjusted'by means of the adjusting screw 35,- which isthreaded into screw threads of the tension element. The rope 34 extendsin the protective sleeve for the cable 3 into the coupling member 2, inwhich it is fixed in the slide 32, which is pushed by the compressionspring 33 into a position in which the slide locks the previouslydescribed stop 25 of the hook portion 21 in its engaged position. Anexcessive force acting in the direction of the arrow x, e.g. during afrontal fall, will result in a movement of the skiing boot at rightangles to the surface of the ski. During this movement, the skiing bootdrives the coupling members 1, 2 so that the springs 37, 38 arecompressed. The rope 34 cannot followthe movement of the cable sections3 and 10 in the direction of the arrow x but moves relative to thecoupling member 2 in the direction of the arrow y until the ropereleases the stop 25 so that the hook portion 21 is released for itsrearward pivotal movement. When the coupling device has thus beenreleased, the compression springs 37, 38 and 33 relax and the hookportion 21 is moved to its locked position. The same effect is achievedin the embodiment of FIGS. 4 to 8 by the action of the coil spring 22.

In the embodiment shown in FIGS. 12 and 13, the hook portion 21 islocked relative to the plates 30' and 31 by a ball detent device 40-42,which co-acts with a detent socket 39 in the hook portion 21. When theadjusted moment :of resistance of the detent device has been overcome bythe moment exerted by the lever arm a on the hook portion 21, the latterwill be pivotally moved rearwardly so that the coupling device isreleased. Owing to the larger stress exerted by the ball detent device,the two plates 30 and 31 are additionally held together by a rivetedbolt 43. This embodiment of the coupling device according to theinvention may be combined with any of the commercial front tighteners.

FIG. 14 shows another arrangement of the coupling device according toFIGS. 12 and 13. In this embodiment the coupling members 1 and 2 areconnected only to short cable lengths 44, which are secured to the ski46 under the ankle with the aid of ring eyelets 45. This embodiment canonly be used in conjunction with front jaws which are applied againstthe front end of the skiing boot 47 and force the same rearwardly.

The embodiments of the invention in which an exclusive property orprivilege is claimed are defined as follows:

1. A coupling device for detachably connecting ends of a cable aroundthe heel of a boot to a ski, in which said cable is attached to the skiin a position forward of the rearrnost portion of said heel; said devicecomprising a pair of coupling members, each attached to a correspondingcable end and each comprising a hook portion, a recess portion and astop portion, the hook portion of each of said coupling members engaginga corresponding recess portion in the other member in a coupled positionto form a yoke extending around said heel, a portion of the engagingsurfaces of said hook and recess portions being approximately parallelwith respect to the longitudinal axis of said ski, so that tightening ofsaid cable in a longitudinal direction with respect to said ski resultsin lateral forces acting on said engaging surfaces to strengthen saidcoupling, each stop portion being spaced from its respective hook andrecess portion and being arranged so that when a predetermined lateralforce on said boot is exceeded, said stop portions mutually engage toform a fulcrum for pivotable uncoupling movement of said couplingmembers.

2. The device of claim 1 further comprising means for locking saidcoupling members in said coupled position from movement in a directionnormal to the upper surface of said ski.

3. The device of claim 2 wherein said locking means comprises a pair ofguide plates connected to one of said coupling members and extendingover said engaging surfaces in said coupled position.

4. The device of claim 1 further comprising means to quick detachablyretain said coupling members in an interengaging position.

5. The device of claim 1 wherein one of said coupling members furthercomprises uncoupling means to uncouple said coupling members when apredetermined longitudinal force on said boot is exceeded.

6. The device of claim 1 wherein said uncoupling means comprises aconnecting member to which one of said coupling members is pivotallymounted to move between a coupled and an uncoupled position with respectto said other coupling member; a stop member slidably mounted in saidconnecting member and connected to one of said cable ends; and resilientmeans normally urging said stop member into blocking engagement withsaid one coupling member to retain same in said coupled position, saidresilient means permitting movement of said stop member out of saidblocking engagement in response to a predetermined longitudinal force onsaid boot being exceeded transmitted via the cable, thus permitting thepivotable movement of said one coupling member to the uncoupledposition.

7. The device of claim 6 further comprising means to regulate the amountof said predetermined longitudinal force required to urge said stopmember out of said blocking engagement.

8. The device of claim 5 wherein said uncoupling means comprises aconnecting member. to which one of said coupling members is pivotallymounted to move between a coupled and an uncoupled position with respectto said other coupling member, a pair of guide plates connected to saidconnecting member and extending over said engaging surfaces in saidcoupled position, a detent member extending through one of said guideplates and into a socket pr-ovided'in said one coupling member in saidcoupled position, and adjustable resilient means urging said detentmember into said socket in said coupled position, said resilient meanspermitting movement of said one coupling member out of engagement withsaid detent member in response to a predetermined longitudinal force onsaid borot being exceeded transmitted by the cable, thus permitting thepivotable movement of said one coupling member to the uncoupledposition.

9. A coupling device for detachably connecting ends of a cable aroundthe heel of a boot to a ski in a position forward of the rearmostportion of said heel, said device comprising a pair of coupling members,each of which comprise a hook portion, a recess portion and stopportion, the hook portion of each of said coupling members engaging acorresponding recess portion in a coupled position to form a yokeextending around said heel, one of said coupling members being connectedto one of said cable ends; a connecting member to which the other ofsaid coupling members is pivotally mounted to move between a coupled andan uncoupled position with respect to said one coupling member; stopmember slidably mounted in said connecting member and connected toanother of said cable ends; and resilient means normally urging saidstop member into blocking engagement with said other coupling member toretain same in said coupled position, said resilient means permittingmovement of said stop member out of said blocking engagement in responseto a predetermined longitudinal force on said boot being exceededtransmitted via the cable, thus permitting the pivotable movement ofsaid other coupling member to the uncoupled position.

10. The device of claim 9 further comprising means for locking saidcoupling members in said coupled position from movement in a directionnormal to the upper surface of said ski.

11. The device of claim 10 wherein said locking means comprises a pairof guide plates connected to one of said coupling members and extendingover said engaging portions in said coupled position.

12. The device of claim 9' further comprising means to quick detachablyretain said coupling members in an inter-engaging position.

13. The device of claim 9 further comprising means to regulate theamount of said predetermined longitudinal force required to urge saidstop member out of said blocking engagement.

14. A coupling device for detachable connecting ends of a cable-aroundthe heel of a boot to a ski in a position forward of the rearmostportion of said heel, said device comprising a pair of coupling members,each of which comprise a hook portion, a recess portion and stopportion, the hook portion of each of said coupling members engaging-acorresponding recess portion in a coupled position to form a yokeextending around said heel, one of said coupling members being connectedto one of said cable ends; a connecting member to which the other ofsaid coupling members is pivotally mounted to move between a coupled andan uncoupled position with respect to said one coupling member; anotherof said cable ends being connected to said connecting member; a pair ofguide plates connected to said connecting member and extending over saidengaging surfaces in said coupled position, a detent member extendingthrough one of said guide plate and into a socket provided in said othercoupling member in said coupled position, and resilient mean urging saiddetent member into said socket in said coupled position, said resilientmeans permitting movement of said other coupling member out ofengagement With said detent member in response to a predeterminedlongitudinal force on said boot being exceeded transmitted by the cable,thus permitting the pivotable movement of said other coupling member tothe uncoupled position.

15. The device of claim 14 further comprising means to regulate theamount of said predetermined longitudinal force required to move saidother coupling member out of engagement with said detent member.

References Cited by the Examiner UNITED STATES PATENTS OTHER REFERENCESv Marker German Application 1,099,414 printed Feb. 9, 1961.

BENJAMIN HERSH, Primary Examiner.

MILTON L. SMITH, Examiner.

1. A COUPLING DEVICE FOR DETACHABLY CONNECTING ENDS OF A CABLE AROUNDTHE HEEL OF A BOOT TO A SKI, IN WHICH SAID CABLE IS ATTACHED TO THE SKIIN A POSITION FORWARD OF THE REARMOST PORTION OF SAID HEEL; SAID DEVICECOMPRISING A PAIR OF COUPLING MEMBERS, EACH ATTACHED TO A CORRESPONDINGCABLE END AND EACH COMPRISING A HOOK PORTION, A RECESS PORTION AND ASTOP PORTION, THE HOOK PORTION OF EACH OF SAID COUPLING MEMBERS ENGAGINGA CORRESPONDING RECESS PORTION IN THE OTHER MEMBER IN A COUPLED POSITIONTO FORM A YOKE EXTENDING AROUND SAID HEEL, A PORTION OF THE ENGAGINGSURFACES OF SAID HOOK AND RECESS PORTIONS BEING APPROXIMATELY PARALLELWITH RESPECT TO THE LONGITUDINAL AXIS OF SAID SKI, SO THAT TIGHTENING OFSAID CABLE IN A LONGITUDINAL DIRECTION WITH RESPECT TO SAID SKI RESULTSIN LATERAL FORCES ACTING ON SAID ENGAGING SURFACES TO STRENGTHEN SAIDCOUPLING, EACH STOP PORTION BEING SPACED FROM ITS RESPECTIVE HOOK ANDRECESS PORTION AND BEING ARRANGED SO THAT WHEN A PREDETERMINED LATERALFORCE ON SAID BOOT IS EXCEEDED, SAID STOP PORTIONS MUTUALLY ENGAGE TOFORM A FULCRUM FOR PIVOTABLE UNCOUPLING MOVEMENT OF SAID COUPLINGMEMBERS.